Epoxy resin curing agent, preparation method, epoxy resin composition and application

Abstract

The invention discloses an epoxy resin curing agent, a preparation method, an epoxy resin composition and application. The structure of the curing agent is shown as a formula I, the curing agent contains reactive functional groups with different activities, the epoxy resin composition prepared from the curing agent can disperse reaction heat, the molecular structure contains aromatic rings, alkoxy and siloxy at the same time, epoxy resin cured products are endowed with excellent strength and impact toughness, and the curing agent can be used in the field of castable for electrical equipment, and is especially suitable for preparation of electronic and electrical product casting parts.

Description

technical field [0001] The invention belongs to the technical field of epoxy resin, and relates to an epoxy resin curing agent, an epoxy resin composition and its application in castings, especially electronic and electrical castings. Background technique [0002] Epoxy resin has excellent comprehensive properties and is often used to prepare various castings. It is mainly used in capacitors / resistors / TVs and transformers in electrical manufacturing to make electrical parts airtight, fireproof, moisture-proof, and corrosion-resistant. However, there are still some significant shortcomings in the use of epoxy resin for casting. First, when large-scale castings are used, the resin curing reaction will generate a lot of heat, which will cause the core to burn, reduce the strength of the casting material, and various properties such as corrosion resistance; The impact strength of epoxy resin is poor, and problems such as fracture and peeling are prone to occur during the transpo...

AI Technical Summary

Problems solved by technology

However, there are still some significant shortcomings in the use of epoxy resin for casting. First, when large-scale castings are used, the resin curing reaction will generate a lot of heat, which will cause the core to burn, reduce the strength of the casting material, and various properties such as corrosion resistance; The impact strength of the epoxy resin is poor, and it is easy to break, peel off and other problems during the transportation / installation / use of the casting, which makes the package invalid; the third is that the thermal conductivity of the epoxy resin is poor, and the heat generated under high-frequency work cannot be released in time. Local overheating causes reduced reliability or even permanent damage to the device

[0003] For problem 1, in the prior art, different active curing agents such as aromatic amines and aliphatic amines are used to mix and cure epoxy resins. However, due to the poor compatibility between aliphatic amines and epoxy resins, it is easy to overflow and cause incomplete reaction, which will also lead to cured products. reduced performance

[0004] For problem 2, in order to improve the toughness of packaging materials, patent CN107629413A forms bacterial cellulose and styrene-butadiene rubber to form a flexible composite energy dissipation system, which is added to epoxy resin to improve the toughness and anti-vibration performance of packaging materials, but the hybrid powder and Epoxy resins have poor compatibility, which will lead to a decrease in the strength and other properties of the material.

[0005] Aiming at problem 3, in order to increase the thermal conductivity of encapsulated epoxy resin, patent CN103951941A and patent 104497482A etc. disclose the preparation method of thermally conductive epoxy resin, by adding inorganic thermally conductive fillers to it, the thermal conductivity of epoxy resin can be effectively improved, but due to the inorganic Fillers have poor compatibility with epoxy resins, and both require pre-surface treatment, which makes the preparation steps cumbersome

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